Implement SubroutinesVisitor

build.sh

@@ -5,4 +5,4 @@ set -x
 
 antlr4="java org.antlr.v4.Tool"
 
-$antlr4 -Dlanguage=Python3 fortran.g4
+$antlr4 -Dlanguage=Python3 -no-listener -visitor fortran.g4

fortran_parser.py

@@ -2,7 +2,6 @@
 from antlr4.error.ErrorListener import ErrorListener
 from fortranParser import fortranParser
 from fortranLexer import fortranLexer
-from fortranListener import fortranListener
 
 class SyntaxErrorException(Exception):
     pass
@@ -15,13 +14,17 @@ def syntaxError(self, recognizer, offendingSymbol, line, column, msg, e):
         print("line", line, ":", column, "at", offendingSymbol, ":", msg)
         raise SyntaxErrorException("Syntax error.")
 
-def parse(source, rule="root"):
+def get_parser(source):
     stream = antlr4.InputStream(source)
     lexer = fortranLexer(stream)
     tokens = antlr4.CommonTokenStream(lexer)
     parser = fortranParser(tokens)
     parser.removeErrorListeners()
     parser.addErrorListener(VerboseListener())
+    return parser
+
+def parse(source, rule="root"):
+    parser = get_parser(source)
     try:
         tree = getattr(parser, rule)()
     except SyntaxErrorException:

list_subroutines.py

@@ -0,0 +1,21 @@
+from fortranParser import fortranParser
+from fortranVisitor import fortranVisitor
+from fortran_parser import get_parser
+
+class SubroutinesVisitor(fortranVisitor):
+
+    # Visit a parse tree produced by fortranParser#subroutine.
+    def visitSubroutine(self, ctx:fortranParser.SubroutineContext):
+        print("subroutine", ctx.ID().getText())
+        return self.visitChildren(ctx)
+
+def main():
+    filename = "examples/random.f90"
+    source = open(filename).read()
+    parser = get_parser(source)
+    tree = parser.root()
+    v = SubroutinesVisitor()
+    v.visit(tree)
+
+if __name__ == "__main__":
+    main()